Initial revision of FileReference.

git-svn-id: https://svn.microneil.com/svn/CodeDweller/branches/adeniz_1@60 d34b734f-a00e-4b39-a726-e4eeb87269ab

filesystem.cpp

+// \file filesystem.cpp
+//
+// Copyright (C) 2014 MicroNeil Research Corporation.
+//
+// This program is part of the MicroNeil Research Open Library Project. For
+// more information go to http://www.microneil.com/OpenLibrary/index.html
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2 of the License, or (at your
+// option) any later version.
+//
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+// more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+// Place, Suite 330, Boston, MA 02111-1307 USA
+//==============================================================================
+
+#include <stdexcept>
+
+#include "filesystem.hpp"
+
+namespace CodeDweller {
+
+  FileReference::FileReference(std::string fileName) :
+    name(fileName),
+    timestamp(0),
+    size_bytes(0),
+    fileExists(false),
+    fileIsDirectory(false) {
+
+    refresh();
+
+  }
+
+  void FileReference::refresh() {
+
+    // Load path if necessary.
+    if (path.empty()) {
+
+      char *realPath = realpath(name.c_str(), NULL);
+
+      if (NULL == path) {
+
+        // Nothing to do if the file doesn't exist.
+        if (ENOENT == errno) {
+          return;
+        }
+
+        // Something went wrong.
+        throw std::runtime_error("Error checking file \"" + name "\":  " +
+                                 getErrorText());
+
+      }
+
+      path = *realPath;
+      free(realPath);
+
+    }
+
+    // Load info.
+    struct stat statBuffer;
+
+    int status = stat(path.c_str(), &statBuffer);
+
+    if (-1 == status) {
+
+      // File no longer exists.
+      if (ENOENT == errno) {
+        reset();
+        return;
+      }
+
+      // Something went wrong.
+      throw std::runtime_error("Error updating status of file \"" +
+                               path "\":  " + getErrorText());
+
+    }
+
+    modTimestamp = statBuffer.st_mtime;
+    size_bytes = statBuffer.st_size;
+    fileExists = true;
+    fileIsDirectory = S_ISDIR(statBuffer.st_mode);
+
+  }
+
+  void FileReference:: reset() {
+    modTimestamp = 0;
+    size_bytes = 0;
+    fileExists = false;
+    fileIsDirectory = false;
+  }
+
+  time_t FileReference::ModTimestamp() const {
+    return modTimestamp;
+  }
+
+  long FileReference::Size() const {
+    return size_bytes;
+  }
+
+  std::string FileReference::FullPath() const {
+    return path;
+  }
+
+  time_t FileReference::exists() const {
+    return fileExists;
+  }
+
+  time_t FileReference::isDirectory() const {
+    return fileIsDirectory;
+  }
+
+  std::string FileReference::getErrorText() {
+
+#ifdef _WIN32
+    LPVOID winMsgBuf;
+    DWORD lastError = GetLastError(); 
+
+    FormatMessage(
+		  FORMAT_MESSAGE_ALLOCATE_BUFFER | 
+		  FORMAT_MESSAGE_FROM_SYSTEM |
+		  FORMAT_MESSAGE_IGNORE_INSERTS,
+		  NULL,
+		  lastError,
+		  MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
+		  (char *) &winMsgBuf,
+		  0, NULL );
+
+    std::string errMsg((char *) winMsgBuf);
+
+    LocalFree(winMsgBuf);
+    return errMsg;
+#else
+    return strerror(errno);
+#endif
+  }
+
+}

filesystem.hpp

+// \file filesystem.hpp
+//
+// Copyright (C) 2015 MicroNeil Research Corporation.
+//
+// This program is part of the MicroNeil Research Open Library Project. For
+// more information go to http://www.microneil.com/OpenLibrary/index.html
+//
+// This program is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License as published by the
+// Free Software Foundation; either version 2 of the License, or (at your
+// option) any later version.
+//
+// This program is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+// more details.
+//
+// You should have received a copy of the GNU General Public License along with
+// this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+// Place, Suite 330, Boston, MA 02111-1307 USA
+//==============================================================================
+
+/*
+  \brief The filesystem module provides classes to access the filesystem.
+*/
+
+#ifndef FILESYSTEM_HPP
+#define FILESYSTEM_HPP
+
+#include <ctime>
+
+#include <string>
+
+namespace CodeDweller {
+
+  /** Abstracts OS specifics for identifying a file and provides
+      access to meta data.
+  */
+  class FileReference {
+
+  public:
+
+    /** Initialize with the name of the file.
+
+        @param[in] fileName is the name of the file.
+    */
+    FileReference(std::string fileName);
+
+    /** Return timestamp.
+
+        @returns the epoch modification time for file when
+        FileReference was created or last refreshed, or zero if the
+        file doesn't exist.
+
+    */
+    time_t ModTimestamp() const;
+
+    /** Get the file size.
+
+        @returns the size of file when FileReference was created or
+        last refreshed, or 0 if the file doesn't exist.
+    */
+    long Size() const;
+
+    /** Get full path.
+
+        @returns a fully referenced path to the file.
+    */
+    std:: string FullPath() const;
+
+    /** Refreshes the FileReference object with the current data on the file
+        system.
+    */
+    void refresh();
+
+    /** Check if the file exists.
+
+        @returns true if the file reference name exists in the file
+        system, false otherwise.
+
+        @throws std::runtime_error if an error occurs.
+
+    */
+    bool exists() const;
+
+    /** Check if the file is a directory.
+
+        @returns true if the name provided on construction resulted in
+        finding a directory not a file, and false otherwise or if the
+        file doesn't exist.
+    */
+    bool isDirectory() const;
+
+  private:
+
+    /// Return text for the most recent error.
+    //
+    // \returns Human-readable description of the most recent error.
+    //
+    static std::string getErrorText();
+
+    /** Name provided to constructor. */
+    std::string name;
+
+    /** Full path. */
+    std::string path;
+
+    /** Timestamp. */
+    time_t modTimestamp;
+
+    /** Size in bytes. */
+    long size_bytes;
+
+    /** True if the file exists, false otherwise. */
+    bool fileExists;
+
+    /** True if the file is a directory, false otherwise. */
+    bool fileIsDirectory;
+
+  };
+
+}
+
+#endif // FILESYSTEM_HPP